Mandrel



2 Sheets Sheet 1. SKER.

Patented Dec. 1, 1885.

(No Model.)

S. P. M. TA

MANDRE EEE UNITED j STATES PATENT OFFICE.

STEPHEN P. M. TASKER, OF PHLADELPHIA, PENNSYLVANIA.

MANDREI..

SPECIFICATION forming part o1 Letters Patent No. 331,570, dated December 1, 1885.

Application `tiled Juno 1R, 1885. Serial No.169,1052. (No modcLi To all whom it may concern: j

Be it known that I, STEPHEN P. M. TAsKnR,

a citizen of the United States, residing in the v specification.

Myinventionrelates to theclass of mandrels which are known as rolle'r-mandrels, and which are providedwith ellipsoidal frictionrolls mounted in bearings in a stock or'case, such a mandrel having been invented by me and patented to me in and by Letters Patent of the United States No. 151,323, dated May 26, 1874:. 1

The intention of the employment of a mandrel of the foregoing class is to obviate friction between the interior surfaces of the tube and the ball of the mandrel, and to permit of the more ready passage of the tube over the mandrel, and withdrawal of the mandrel from the tube.

My present mandrel is an improvement upon that patented to me. i

1 A device employing threerolls and embodying a good form of my improvements is represented in the accompanying drawings, and described in this specification, the particular subject-matter claimed as novel being hereinafter denitely specified. i

In the accompanying drawings, Figure l is a top plan view of a mandrelconveniently embodying `my improvements and having three rolls. Fig. 2 is a front or face viewV of the same. Fig. 3 is a rear view of the same, or a view from behind of the socket into which the mandrel-rod is entered. Fig. 4 is a cen tral vertical front elevation, section being supposed in a vertical plane projected on the dotted line x x of Fig. 1-that is to say, in the common' plane of the axes of the rolls. Fig. 5 is a central vertical front elevation of a mandrel conveniently embodying my improvements and having four rolls. Fig. 6 is a similar view of a mandrel likewise conveniently embodying my improvements and having iive rolls.

ln the rst four figures similar letters of reference indicate corresponding parts.

Referring now to the rst four gures of the drawings, A A A2 are three euipsoidai metal rolls mounted in a stock or mandrelhead preferably composed of as many sections as there are rolls, and it is to be understood that three, four, or more rolls may be employed without departure from my invention. The stock represented in the said rst four gures of the drawings is, however, formed of three sections, B B B2, which'are conveniently connected together by flanges b bfbz, which are .skeleton shell or mandrel-head, the circle of which, considered with reference to a central vertical diametric plane, is coincident with the common plane of the axes of the rolls, and in .effect completed by the peripheries of the rolls, as shown in Figs. 2, 3, and 4. -Each'of the rolls is, as stated, ellipsoidal, spherical, vor ovoid-their axes all lie in or close to a common plane-and at each of its extremities each roll is mounted or journaled with respect to the sections of the stock by means of journals or axles D, which may either be formed upon the rolls or, as represented in the drawings, formed upon or connected with the sections of the stock. The sections are prolonged to the rear to circumscribe-asocket, E, for the mandrel-rod, upon which the mandrel as an entirety is mounted, and by which it is actuated. Each roll, as a reference to Fig. 4

will clearly show, hasormay have at -or near each of its endsa point of contact withthe two adjacent rolls, from whichit results that the pressure upon the rolls when the tube is caused to pass over the mandrel is resisted more perfectly than would be the case were the whole pressure exerted upon the journals, and the journals themselves thereby relieved. lt is, as stated, possible to employ a greater number of rolls than three, in which case of course thesections of the stock are correspondingly increased in number.

In Fig. 5 ofthe drawings l have represented the mandrel as provided with four rolls, and in Fig. 6 as provided with five rolls. These forms are not su ch as l prefer; but they are ICC clearly .within my invention, and for such reason illustrated. The shape and configuration of the rolls, as well as the outer surfaces of the sections of the stock, may, moreover, be made to correspond to the interior conguration of tubes which are not cylindriform.

The mandrel is, in connection with external rolls or dies, adapted for use in the manufacture of all kinds of malleable metal tubes rfrom either hot or cold metal. It will be observed that the bellied portions of the sections of the stock lie below the circle circumscribing longitudinally the three rolls, and this is important, because the sections are not intended to bearagainstthe bore of the tube.

In the use of the mandrel it will be understood that after the tube has been rolled it must berotated to bring that portion of its `interiorsurfaee which in the previous pass has comeover the sections of the stock over the centers or rolling-surfaces of the rolls, and that this operation may be repeated as often as desirable, or until the tube as to every part of 'its interiorsurface has been acted upon by the rolls. It isalso obvious that the sectional construction ofthe stock permits me to readily introduce the rolls and remove them for repair or renewal.

I am aware that roller-mandrels having three or more rolls the axes of which dov not lie in or close to a common plane, but are approximately parallel with each other and with the axis of the tube through which they operate,'have heretofore been known. I do not lay any claim, therefore, to the use of the rolls, except as herein described-that is to say, when their axes lie in or close to a comlmon plane, and are transverse or right angular to rather than parallel with the axis of the tube-and except as provided With bearings at their extremities, as opposed to being simply laid in suitably-shaped sockets.

Having thus described my invention, I claimy l. A mandrel for rolling metal tubes, consisting of three or more ellipsoidal rolls, the axes of which lie in or close to a common plane, in combination with and mounted by bearings at their extremities in a stock or frame.

2. A mandrel for rolling metal tubes, consisting of three or more ellipsoidal rolls, the axes of which lie in or close to a common plane, in combination with and mounted by lbearings atv their extremities in a sectional stock or frame, substantially as and for the purposes set forth.

3. A mandrel for rolling metal tubes, consisting of three or more ellipsoidal rolls having bearings at their extremities, suitably mounted in a sectional stock or case, with all of their axes in or close to the same plane,but with the axis of each roll at an angle to the axes of adjacent rolls, substantially as and for the purposes set forth.

4. A mandrel for rolling metal tubes, consisting of the combination of three or more rolls having bearings at their extremities, a stockv or frame consisting of as many sections as there are rolls, and means for uniting the sections, substantially as and'for the purposes set forth.

5. In a roller-mandrel, the combination of three or more ellipsoidal rolls ,with a sectional case composed of a number of curved sections corresponding in number with the rolls, and provided with flanges whereby the said sections may be united, substantially as and for the purposes set forth.

6. The combination, in a roller-mandrel, of three'or more ellipsoidal rolls, a sectional case composed of a number of curved sections corresponding in number-with the rolls and provided with flanges, and bolts for uniting the flanges of the sections, substantially as and for the purposes set forth.

7. The combination, in aroller-mandrel, of

three or more ellipsoidal rolls, a series of segmental sections containing the bearings for the rolls, and interposed between the extremities of said rolls, and suitable means for uniting the said sections together, substantially as set forth.

8. In a roller-mandrel, the combination of a stock composed of a series of segmental sections adapted to contain the bearings of the rolls and to beinterposed between the extremities of said rolls, means for uniting theA said sections together, and a series of ellipsoidal rolls corresponding in number to the number of the sections of the stock, substantially as and for the purposes set forth.

In testimony whereof Ihave hereunto signed my name this 16th day of June, A. D. 1885.

STEPHEN P. M. TASKER. In presence of- J. BoNsALL TAYLOR, F. NORMAN DIxoN.

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